What We Study

NIEHS intramural scientists have defined descriptive terms of particular relevance to their own research, and have ranked those terms accordingly. This search feature obtains best-matches with the terms you choose, and shows an overall score based on the scientific rankings.

Research

NIEHS research uses state-of-the-art science and technology to investigate the interplay between environmental exposures, human biology, genetics, and common diseases to help prevent disease and improve human health.

Research Highlights

The vision of the NIEHS is to use environmental health sciences to understand human disease and improve human health. Use the search box to see research highlights from NIEHS scientists since its founding in 1966.

Technology Transfer

Visiting NIEHS

About NIEHS

The National Institute of Environmental Health Sciences (NIEHS) is expanding and accelerating its contributions to scientific knowledge of human health and the environment, and to the health and well-being of people everywhere.

NIEHS grantees report that cells in the lungs of rats converted short and long silver nanowires into shorter lengths that were fully taken up by lung cells and led to lung inflammation. The study provides new insights into possible health risks linked with silver nanomaterials, which are increasingly used in industrial and domestic products, such as odor-resistant socks, personal care products, respiratory devices, food storage boxes, computers, and cleaning sprays.

To study the respiratory toxicity of short and long silver nanowires — 1.5 microns and 10 microns in length, respectively — the researchers instilled nanowires of each length into the lungs of rats. Within one day of instillation, both short and long nanowires were taken up and degraded by lung macrophages, a type of white blood cell that engulfs and digests cellular debris, and by cells lining lung alveoli, the site of oxygen exchange. Using three-dimensional scanning electron microscopy, the researchers observed a small, but significant, reduction of nanowire lengths inside cells.

The researchers also observed increased lung inflammation after instillation of both types of nanowires. Mice receiving the long nanowires showed a greater and longer-lasting degree of lung inflammation and bronchial hyperreactivity.